oops, sorry, the previous email was a mistake :)
Bruce
On Fri, 30 May 2008, Tim
Behrens wrote:
> if bval =0, bvec can be anything (as it will be multiplied by 0!), but it has
> to be there.
>
> T
> On 30 May 2008, at 16:01, Erik O Hanlon wrote:
>
>> Hello Ted,
>>
>> Thanks for the quick response. Much appreciated. I have 16 values in my
>> bvec file as you say but I thought that when normalized the sum of the X Y
>> and Z values had to be 1. Does this mean that the bvec entries that match
>> the bval of 0 (in my case the first value in the x,y and z rows) don't
>> have to sum to one?
>>
>> Thanks again for your reply
>>
>> best
>>
>> Erik
>>
>>
>> On 30/05/2008, Ted Yanagihara <[log in to unmask]> wrote:
>> On May 30, 2008, at 10:35 AM, <ERIK> <O'Hanlon> <[log in to unmask]> wrote:
>>
>> Hello Fsl experts,
>>
>> Just wondering if somone could clear up the format of the bvec and bval
>> files. In the bval file I have 1 b0 and 15 b800 values, my bvec file has
>> sixteen entries for x y and Z. Should there be zeros in the bvec file
>> where the b0 entry is?
>>
>> Yes
>>
>> My b0 value comes first so does this mean that the
>> first entry in the bvec file should be x= 0 y= 0 and z=0. What will the
>> effect be if these values are non zero.
>>
>> The analysis wont run because there will be 16 entries in bvals and 15 in
>> bvecs. Don't forget to run dtifit and check the orientations of V1 (before
>> running bedpost).
>>
>> good luck!
>>
>> ted
>>
>>
>> Thanks for any help you can offer.
>>
>> best
>>
>> Erik
>>
>>
>>
>>
>> --
>> Erik O'Hanlon
>> School of Psychology and Institute of Neuroscience,
>> 3r.d Floor Rm. 3.23,
>> The Llyod Institute,
>> University of Dublin,
>> Trinity College Dublin,
>> Dublin 2,
>> Ireland.
>>
>> Tel. + 353-1-8964801
>> Fax. +353-1-896 3183
>> E-mail: [log in to unmask]
>
>
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